Hi, Adam - that image you linked isn't viewable on this website since it's kept on your hard drive. You'll need to upload it to an image hosting website like imgur and then link it for us to view it here.
Anyway, there's a reason that top-down RPGs don't usually have east-west doors. They're hard to see because of the angle. But I would suggest either eliminating east-west doors or putting a very big gap in the wall where the door is. Maybe have the door jutting out into the hallway a lot to make it really obvious.